<template>
    <div class="app">
      <h3>我是APP组件</h3>
      <Suspense>
        <template v-slot:default>
          <Child />
        </template>
        <template v-slot:fallback>
          <h3>loading...</h3>
        </template>
      </Suspense>
    </div>
</template>

<script>
  // import Child from './components/Child'; // 静态引入
  import { defineAsyncComponent } from 'vue'; 
  const Child = defineAsyncComponent(()=>import('./components/Child')) // 异步（静态）引入
  export default {
    name:'App',
    components:{Child}
  }
</script>

<style>
  .app{
    background-color: gray;
    padding: 10px;
  }
</style>